Various climate indices have been utilized to describe the environmental conditions within the reindeer herding areas, including large scale climate indices such as NAO/AO and local weather data from the Meteorological Institute. However, satellite based observation of vegetation has so far been most successful in local conditions that affect food availability and success reindeer.

We used remotely sensed vegetation green-up to index climatic conditions and plant productivity as this predictor appears to be the one with the highest spatial resolution and best predictive power in terms of recruitment and body mass of semi-domesticated reindeer. Based on 16 day and 250 meter resolution MODIS EVI data we estimated spring onset and plant productivity within the calving and summer pastures.